Airplane wing



Mmh'z, 1933. F, G, BAUM 5 1,900,688

AIRPLANE WING I Filed March 6, 1930 2 Sheets-Sheet 1 l// I I (I ENVENTOR MM ATTORNEY 2 Sheets-Sheet 2 ATTORNEY March 7, 1933. F, G. BAUM AIRPLANE WING Filed March 6, 1930 m fii m, i w 1, m 1H Y MM 98 7 H i 9 2 M. m M MJKMHH M H 6 f) WI .\H v. Z 0W 7 7 z z a W fi 5.

Patented Mar. 7, 1933 UNITED STATES- PATENT OFFICEJ FRANK G, BLUE, SAN FRANCISCO, CALIFORNIA AIRPLANE WING .Appllcation filed larch 6, 1980. Serial No. 488,565.

, ing speed, the take off and landing speeds are correspondingly high. Attempts have been made to design a wing which would permit a high cruising speed and a relatively low take off and landing speed, and it is to such a wing that my invention relates.

Heretofore, such wings resulted in sacrificing some important feature of the standard construction, such as the rigidity of the wing structure, or where the wing structure is inflexible, the construction of the wing is such that the cruising speed of the airplane is materially affected.

By my invention, I am enabled to increase the lifting power of the wings at take off and landing without materially aflectin the cruising speed of the airplane or sacri 'cing the strength inherent in a rigid wing structure. I employ a construction in which auxiliary wings adjustable. to impart a greater or less longitudinal curvature thereto are secured tothe trailing end of the wings extendin from the fuselage at either side thereof? A feature of my invention is the fact that the disposition of the auxiliary wings may be adjusted'manually or automatically in accordance with the speed of the airplane rel- -ative to the surrounding air.

Another feature of my invention is the fact that the auxiliary wings comprise a plurality of independent sections which are secured to the wings of the airplane for retational movement about their longitudinal axis. The sections of the auxiliary'wings may be rotated to cause the air to flow between the sections and create a braking effeet causedby the friction between theair and the surfaces of the auxiliary wing sections.

Another feature of my invention is the fact that the longitudinal curvature of the auxiliary wings is adjusted by fluid under pressure. Specifically, I provide an airplane having the usual fuselage. To the fuselage the wings are secured and extend therefrom at either side thereof. Auxiliary wings which .are adjustable to impart a curvature thereto are secured to the trailing end of the first mentioned wings.- The auxiliary wings consist of a plurality of independent sections of which are rotatably secured to the first mentioned or main wings. The adjustment of the auxiliary wings to change the curvature thereof may be controlled manually or auto: matically in accordance with the speed of the airplane relative to the surrounding air, and the sections which make up the auxiliar wings may be rotated to cause a brakinge fct. In starting, the auxiliary wings are curved downwardly and the sections are in alignment. The downward curvature of the auxiliary wings increases. the lifting power of the wings so that the airplane will take off at a relatively low speed, As the air plane takes off and gathers speed, the auxillary wings gradually straighten out until the cruising speed is reached at whichspeed the auxiliary wings form a continuation of the main wings. As the speed of the airplane decreases, the auxiliary wings again curve downwardly in accordance with the decreasing\speed of the airplane. When the maximum curvature 'of the wings has been reached, or previous thereto if desired, the sections of the auxiliary wings are rotated to set up friction between the air and the surfaces of the auxiliary wing sections and create a braking effect to decrease the speed of the airplane before landing. 7

Other features of my invention will appear from the following particular descriptionof one embodiment thereof as illustrat ed in the accompanying drawings in which:

Fig. 1 is a plan of an airplane with parts broken away;.

taken on the line 4-4 of Figure 3;

F' 5 is a fragmentary section taken on i the lfie 5-,5 of Figure 1;

in e

Fig. 6 is a longitudinal section of the device for automatically controlling the adjustment of the auxiliary wings;

Fig. 7 is a lon 'tudinal section of the devicefor manual y controlling the adjustment of the auxiliary wings;

Fig. 8 is awiring diagram of the system for controlling the adjustment of the auxiliary wings; and

Fi 9 is an end elevation of a wing, the auxi ary win secured thereto being shown in section an illustrating a modified form of control.

In the drawings, I'have shown my invention as embodied in an airplane of the monoplane t pe. The invention is, however, equaly app 'cable to the other types of airplanes such as biplanes and also. to hydroplanes. The air lane shown com rises a fusela e 1 in whic the motor 2, t e shaft of w ich carries the propeller 3, is mounted. To the fuselage wings 4 and 5 are secured and'extend therefrom at either side thereof. Auxilia wings which consist of a plurality of ndent sections 6 are secured to the traihng end of the wings 4 and 5.

Each of the sections of the auxiliary wings has a curved tubular central frame member 7, normally curved as shown in Figure 2 and as shown in broken lines in Figure 3, and having suflicient inherent strength to retain this normal shape against the pressure of the air. The outer end, that is, the trailing end of the tubular frame member is closed. At spaced intervals along the central tubular frame members 7, there are lateral fins 8 secured thereto which support the fabric covering 9. At the inner end the tube enters the wmg of the airplane and is connected to a common fluid sup ly pipe 10, the connection between the supply pipe and the tube being such as to permit rotational movement of the tube. The tube 7 is rotatably secured to the wing by collars 11 secured to the tube on opposite sides of the end wall 12' of the wing. Within the wing of the airplane, between the inner collar 11 and the common supply pipe 10, a pinion 12 is secured to the tube 7 for rotation therewith, the purpose of which will be hereinafter described.

The common fluid supply pipe 10, common to the tubesin all of the sections 6 of the auxiliary wings, is connectedby means of a pipe line 14 to a rotary pump 15. The pump 15 is secured to the frame of the motor 2 and is connected to the motorfor operation thereby. Intermediate the pump 15 and the common supply pipe 10 in some such position as shown, a valve 16 is interposed in the pipe 14. The valve 16 is a two way valve and has a connection to a reserve tank 17 which in turn is connected to the intake end of the pump 15. As the valve is moved in one direction the common sup 1y pipe is connected to the high pressure end of the pump 15 and the pressure is transmitted through the fluid in. the system to the tubular frame members 7 which tend to straighten out and when the valve 16. is fully opened in this direction and the full pressure of the pump transmitted to the frame members 7 they straighten out the sections of the auxiliary wings to form a continuation of the wings 4 and 5. When moved to close the connection between the tubular frame members 7 and the high pressure side of the pump 15, the valve 16 opens a connection between the tubular frame members, and the tank 17, thereby releasing the pressure and permitting the tubular frame members to assume their normal curvature. The valve 16 is electrically actuated, and may be controlled by a manually actuated device or a device which is responsive to the soeed of the airplane relative to the surrounding air.

The device for manually controlling the valve 16 is shown in Figure 7 in which there is shown a cylinder 18 having a plunger 19 extending through one end thereof. The cylinder 18 is formed from insulating material such for example as hard rubber. The plunger 19, which is hollow, rides upon a rod 20 secured in the cylinder 18 and is resiliently urged to the inoperative position by a convolute spring 21 surrounding the rod 20 and actin between the inner end of the plun er and t e opposite end wall of the cylin er. On the inner end of the plunger 19, there is secured a contact collar 22 which in the inoperative position' of the lunger contacts with a contact brush 23 to wiiich there is connected an external binding 0st 24, Upon pressing the plunger inwar ly against the action of the sprin 21, the collar becomes disconnected from t e brush 23 and contacts with a variable resistance 25 secured to the inner wall of the cylinder 18. The resistance is connected to an external binding post 26. A binding post 27 connected to the rod 20 furnishes an electrical-connection to the plun er 19, and as the plunger is depressed, the e ectrical resistance between the connections to the binding posts 26 and 27 is decreased and the valve 16 is actuated accordingly.

The device for automatically controlling the valve 16 in accordance with the speed of the airplane is shown in Figure 6. This device which consists of a cylinder 28 enclosing a centrifugal device 29 is adapted tolbe placed on the leading edge of one of the wings 4 or 5. Preferably, the device issecured to the wing nearthe outer edge thereof so as not to come within the influence of the airplane propeller 3. To the shaft 30 of the centrifu gal device 29 which extends through one end of the casing there is secured a propeller 31 which is driven by the air currents set up by virtue of movement of the airplane relative to the surrounding air. Within the casing 28', a hollow tube 32 is fitted over the shaft 30 and secured to the centrifugal device 29 which moves the tube longitudinally in accordance with the speed ofrotation of the propeller 31 which is proportional to the speed of the airplane. 'To the end of the tube 32, opposite the centrifugal device 29, there is secured a contact 33 which contacts with a resistance coil 34 secured to the inner surface of the cylinder wall. The resistance 34 is connected to a binding post 35 and the tube -32 is connected to a binding post 36 through ergy 39 by a wire 40. The other side of the coil is connected by wire 41 to the binding post 31-of the movable contact 33 of the authe valve coil 38 to which the wire 41 is con nected to the resistance coil 25 of the manual controlling device as indicated by the wire 43. The movable member of the manual control device, that is, the plunger 19 is connected to the source of electrical ener 39 by a wire 44. From the above description, taken in connection with the wiring diagram, it will be apparent that when the manual controlling device is actuated to control the valve 16, the automatic control device is cut out of the circuit from the source of current and when the manual device is inoperative, the resistance coil associated therewith is cut out of the circuit to the control valve 16 and the automatic control device is connected into the circuit. Thus, when the plunger 19 is depressed on the manual control device, the collar 22 moves off of the contact brush 23 and breaks the circuit from the source of current to the automatic control device. Simultaneously with breaking the circuit to the automatic control device, a circuit is completed as follows from the souroe'of electrical energy 39, through wire 44 to movable contact 22 on the plunger 19 of the manual control device, resistance coil 25, wires 43, and 41 to the valve coil 38,

the inoperative position the contact between the plunger and the resistance coil 25 is broken and the contact between the plunger and the contact brush 23 is closed and a circuit completed as follows: frdm the source of electrical energy to plunger 19 through wire 43, contact brush 23, wire 42, resistance coil 34 of the automatic control device, movable contact 32, wire 41 to coil 38 and back to the source of electrical energy through wire 40. Thus, the adjustment of the curva-' ture of the sections of the auxiliary wing sections may be controlled automatically or manually by the pilot, the manual controlling device being placed within reach of the pilot. Rotational movement of the sections of the auxiliary wings is controlled from the cabin of the airplane by means of connections to the pinions 12 secured to the tubular frame members 7. Along each of the wings 4 and 5 in engagement with all of the pinions secured to the tubular frame members of the sections of each of the auxiliary wings there is a rack 45 and a'rack 46 respectively. ,At the longitudinal center of the airplane, the inner ends of the racks 45 and 46 overlap and are offset as shown in Figure 4. On the opposed sides of the offset portions of the racks, gear teeth are formed which engage the teeth on a pinion47 therebetween. The pinion 47 is secured on the end of a shaft48;

On the opposite end of the shaft 48 behind the instrument board there is secured a bevel gear 49 which meshes with a bevel gear 50 secured on a shaft '51. A second gear 52 secured to the end of the shaft 51 op osite to that on which the gear 50.is secured meshes with a gear 53 securedon a shaft-54 upon which there is secured an operating handle 55 within reach of the pilot. Movement of the operatin handle 55 by mitted t rough the train above described to the pinions on the tubular frame members 1 to rotate the sections of the auxiliary wings to cause the air to flow therebetween and create a braking effect due to the retarding force set up by the friction between the air and the surfaces of the sections of the auxiliary wings.

In Figure 9, iary-wing section having a modified construction. In this form, the central frame member 7 extends through a cylinder 56 secured in the wing. Within the cylinder 56 a piston 57 operatively mounted in the cylinder is secured to the frame member 7'. A spring 58 within the cylinder acts on the forward end of the piston to move the piston rearwardly in the cylinder, the common fluid supply 10 being connected to the rear end of the cylinder so that the fluid pressurelacts the pilot is transthere is illustrated an auxilagainst the force of the spring 58. raven- 1 moves rearwardl in the c inder under the action of the spring 58 an when pressure is I the central frame member 7 which extends have their trailing ends raised and lowered drawings and above particularl through a bearing 59 at the end of the wing. As the frame member is drawn forwardly through the bearing 59 it straightens out as shown in Figure 9, and as the frame member 7 is moved rearwardly it assumes its normal curvature. The rack is made sufficiently wide so that the pinion 12" on the central frame member can move with the frame member without becoming disengaged from the rack.

The function and operation of the auxiliar wings is as. follows: At starting, the auxi iary wings. are curved downwardly assuming the normal curvature of the hollow tubular frame members 7 of the sections of the auxiliary wings, as shown in broken lines in Figure 3, the auxiliary wings being in lateral alignment. The downward curvature of the auxiliary wings increases the lifting power of the wings and the air lane will take off at'a relatively low speed. s the airplane takes off and gathers speed, the valve 16 is actuated by the automatic control device to connect thetubular frame members to the high pressure side of the pump 15 and thetu ular frame members tend to strai hten out the sections of the auxiliar wings. Vh the cruising s d is reache the valve 16 is fully opene so that the full pressure developed by the pump 15 is transmitted to the tubular frame members 7 which straighten out sufliciently to cause the auxiliary wing sections to form a continuation of the wings 4 and 5. As the speed of the airplane decreases, the auxiliar wings a ain curve downwardly in accor ance with t e decreasing speed of the airplane. When the auxiliary wings have reached the maximum curvature, or previous thereto, if found desirable, the pilot may move the operating handle to rotate the sections of the wings to create a braking efl'ect to decrease the speed of the airplane for landing. The curvature of theauxiliary wings is additionally at all times under the manual control of-the operator. I

It is obvious .that various changes may be made in the embodiment shown in the described within the principle and scope o n invention as expressed in the appended c aims.

1. In an air lane, incombination with the fuselage and the main wings extending laterally therefrom, auxiliary wings adapted to consisting of a plurality of inde ndent sections secured to the trailing e of the main wings for rotation about t eir glongitudinal axis, means to control the disposition of the trailing edges of the auxiliary win and means for rotating the sections of t e auxiliary wings about their longitudinal axis.

2. In an airplane, in combination with the fuselage and the main wings extending laterally therefrom auxiliary win adapted to have their trailing ends raiser? and lowered consisting of a pluralit of independent sections secured to the trai 'ng edges of the main wings for rotation about their lon itudinal axis, means controlled autoihatical y in response to the speed of the airplane to control the disposition of the trailing ends of the auxiliary wings, and means for rotating the sections of the auxiliary wings.

3. Man air lane, in combination with the fuselage and t e main wings extending laterally therefrom, auxiliary win ada ted to have their trailing ends raise and owered consisting of a plurality of independent sections secured to the trailing ed es of the main wings for rotation about t eir lon tudinal axis, means controlled automaticafiy in response to the spe .of the air lane to control the disposition of the trailmg ends of the auxiliary wings, manual means to control the disposition of the ends of the auxiliary wings including means to render the automatic control means inoperative, and means for rotating the sections of the auxiliary wings.

4. An auxiliary wing section adapted to be secured to the trailing edge of an airplane wing and have its trailing end raised and lowered comprising a longitudinal curved frame member closed atone end, the o posite end being opened and adapted to be connected to a source of fluid under ressure.

5. In an air airplane, in combination with the fusela e and the main win s extending laterally t erefrom, auxiliary wings adapted to have their trailing ends raised and lowered comprising longitudinal curved tubular frame members secured to the trailing edges of the main wings, a source of fluid under pressure connected to the tubular frame members, and means to control the admission of the fluid under pressure to the tubular frame members.

' 6. In an ai lane, in combination with the fusela e and t e main wings extending laterally t erefrom, auxiliary wings comprising a plurality of independentsections, each of the sections having a longitudinal central curved tubular frame member extendin into the trailing edge of the main wings and ing rotatably secured therein for rotation about their longitudinal axis, a source of fluid under pressure connected to the tubular frame members, means to control the admission'of fluid under-pressure to the tubular frame members to vary the curvature thereof, a inion. secured on each ef the ends of the tu ular frame members extending into the main wings, a rack in each of the main wingsenga the pinions on the tubular frame mem rs, and means for moving the rack longitudinally thereof to rotate the sections of the auxiliary win v In witness whereof, I 'ereunto subscribe "my signature. 7

' FRANK G. BAUM. 

